Patent GB-459124-A (GB)
Title: Manufacture of cellulose derivatives and of artificial filaments, film and other shaped structures therefrom
IPC: C08B13/02
Filed: 1935-03-29
Abstract: A cellulose compound substituted by an organic radicle and containing free hydroxy groups capable of binding carbon disulphide, is reacted with less than 20 per cent of carbon disulphide calculated on the weight of the cellulose compound. Suitable cellulose compounds are cellulose ethers containing not more than one alkyl or hydroxy-alkyl, or hydroxy-acid group per 2, 4, 6, or 30 units of cellulose. Solutions of the cellulose ether xanthate obtained by dissolving the cellulose compound in caustic alkali, with or without cooling to 0 DEG  C. or lower, may be brought into an appropriate shape which may be supportless as with artificial silk, straw, films, bands and the like, or supported on rigid or pliable bases as with coatings, layers, impregnations, dressings, and the like, and coagulated by means of one or more coagulating agents, e.g. such as are used for coagulating viscose. The coagulated products may be plasticized, or the shaped solution may be coagulated and plasticized in one bath, e.g. a bath containing not less than 25 per cent and not more than 75 per cent of sulphuric acid.  In an example, 1000 parts of cellulose are etherified at 18--21 DEG  C. in the presence of caustic soda solution with 100--200 parts of ethylene chlorhydrin, 100--280 parts of glycerol a -monochlorhydrin, 100--300 parts of dimethyl sulphate, diethyl sulphate or monochloracetic acid, 55--120 parts of ethylene oxide, 75--150 parts of propylene oxide, or 90--180 parts of glycide, and the reaction mass, with or without addition of more caustic soda, is treated with 140 to 160 parts of carbon disulphide.  The solution obtained is formed into supportless or supported shaped structures, such as artificial threads, films, coatings and the like.  The solution may also be mixed with a dye or pigment and printed on to the fabric, or it may be used for pasting together sheets of paper or cardboard, or fabrics, or for forming thick plates.  In each case the shaped cellulose ether xanthate solution is coagulated, or coagulated and plasticized. Before working up into shaped structures, the solutions may be mixed with viscose, softening agents and the like. In modifications of the above example, the amount of carbon disulphide used for the xanthation amounts to 70 to 100 parts and 40 to 65 parts.  In other examples, other temperatures and proportions of caustic soda, water, and etherifying agents are used in the preparation of the cellulose ether; various methods of forming the xanthate from the cellulose ethers also are described. In other examples, the following etherifying agents, ethyl chloride, propyl chloride, benzyl chloride, and also mixtures of etherifying agents are used.  Specifications 25246/11, [Class 2 (iii)]; 177,810, 200,816, 200,834, 203,346, 203,347, 212,864, 231,807, 231,808, 231,809, 231,810, 231,811, 281,352, 312,197, 323,731, 323,732, 335,906, 335,993, and 335,994, [all in Class 2 (ii)], and 341,843, 341,899, 341,930, 357,121, 357,154, 357,167, 357,526, 357,527, 357,549, 357,595, 367,920, 368,288, 374,964, 385,979, 390,516, 390,517, 390,518, 390,519, 393,932, 408,950, 457,031, 459,122, and 459,123 are referred to.